Steam-tool.



No, 819,727. PATENTED MAY 8, 1906. G. L. GHARVAT.

STEAM TOOL.

APPLICATION FILED NOV. 25. 1902.

NITED STATES PATENT QFFICE.

.STEAIVI-TOOL.

Specification of Letters Patent.

Patented May 8, 1906.

Application filed November 25, 1902. Serial No. 132,729.

To all whom it may concern.-

Be it known that I, CHARLES L. CHARVAT, a citizen of the United States,residing at Peoria, in the county of Peoria and State of Illinois, haveinvented certain new and useful Improvements in SteamTools; and I dohereby declare that the following is a full, clear, and exactdescription of the invention, which will enable others skilled in theart to which it appertains to make and use the same.

This invention has reference to a tool operated through theinstrumentality of steam, compressed air, or like medium.

The object which I have in view is to pro- Vide a power device to whichmay be attached suitable means for tube-cleaning purposes or employed asa pneumatic tool in various ways.

The invention and its uses are fully disclosed in the followingspecification, of which the accompanying drawings form a part, in whichthe separate parts of my improvement are designated by the same numeralsof reference in each of the views, and in which- Figure 1 is alongitudinal section of my device, showing its connection with meanssupplying steam, compressed air, or like medium to the same. Fig. 2 isan end View of the cylinder portion of the device. Fig. 3 is acrosssection of the same. Fig. 4 is a cross-section through thecylinder-head. Fig. 5 is a plan view of the piston and its componentparts. Fig. 6 is a view of one end of the piston. Fig. 7 is alongitudinal cross-section through the piston and its valve parts. Fig.8 is a front elevation of Fig. 1 with an extension of the piston incross-section, and Figs. 9 and 10 illustrate detail views showingmodifications.

The tool comprises a member 1, which serves the purpose of asteam-cylinder, having a cylindrical chamber portion 2, in which isoperatively carried a piston 3, adapted to have a reciprocal movementimparted thereto. The chamber 2 and the piston 3 have their axialcenters disposed to one side of the central bearing-line of the member1, as shown, and in the forward end of the member 1 is provided anaperture 4, through which extends a reduced stem portion 5 of the piston3, and it is to the end or some portion of the stem 5 that it isdesigned to attach operative devices to be actuated by the piston. Thenature of the devices or their connec tions with the stem 5 areimmaterial. As stated above, the tool itself is designed for operativelycarried in the seat portion 6, and

adapted to be shifted so that its opposite sides will alternately abutwith the inner faces of the portions 7. The piston is further providedwith ports 9, alternately employed as inlet and exhaust ports andcommunicate with the slide-valve 8 in the manner shown in Fig. 1, and 10is an exhaustport passing transversely through the piston, andcommunicating therewith is an exhaustport 11, extending at right anglesto the port 10. The exhaust-port 10 is arranged to intermittently andalternately receive exhauststeam through the ports 9, and theexhauststeam passing through the port 10 will enter oppositely-arrangedexhaust-ports 12, extending longitudinally in the walls of the member 1and open out of the end of the member and are so arranged that the port10 will communicate with the ports-12 at all times, and a further meansof exhaust is provided by the port 11, which communicates with anexhaust 13, opening out of the side of the member. I (See Fig. 1.)

The slide-valve 8, which is operatively carried in the transverse seatportions 6, 18 designed to alternately open or close the ports 9 and isprovided with a depressed body part 14, forming a chamber for steampassing through the ports 9 into the ports 10. The ports 9, which, asstated, serve the purpose of inlet and exhaust ports, open out of theside of the piston and, as shown, converge from a point adjacent to theexhaust-port 10 to a point near the opposite ends of the piston. Wherethe ports 9 open out of the pistonthey communicate with chamberedportions 15, which are of suitable depth, width, and length, and both ofsaid chambers are provided with reduced or contracted depressed orchambered port ons 16, the function of which will hereinafter be moreclearly described.

In the portions 7 of the piston I provide longitudinal apertures,(indicated as 17,) and operatively carried through these apertures andextending longitudinally of the piston and crossing the seat portion 6thereof is a rod or stem 18, which, as shown, is longer than the lengthof the piston, for a purpose to be set forth, and the said rod has atransversely-arranged cut-out or seat portion 19, in which is seated theslide-valve 8, whose movement is controlled and governed by the movementof the stem 18, as will become apparent.

20 indicates a head portion of the same diameter as the member 1 andabuts against the end of the member 1 for closing the open end of thechamber 2 and is bolted-or otherwise sutably secured thereto. This headis designed to have attached to it an inlet-pipe 21 or slmlar dev.ce forsupplyng mot .ve medium for actuatng the p..ston, and the head 20 isprovded W'..tl1 a chamber port .on 22, communicatingwith aport 23 of thesame, whch in turn communicates with a port 24, extending longitudinallyin the wall of the member 1, which at a 'sultable point opens out intothe chamber 2 and does at all t.mes admit motive medium into saidchamber and into the seat port-on 6 of the piston 3, (see Figs. 1 and3,) and 25 indicates a'reinforcingblock suitably disposed within thechamber 22 and serves to strengthen this portion of the inner face ofthe head, which is engaged by the end of the rod 18 in its movement, allof which will be more readily set out hereinafter.

To relieve the jar upon the rod 18 and the valve, I have provided uponopposite sides of the valve 8 the short stems 26, which as the valvereaches the end of its stroke in either direction wLll enter chambers27, formed within the portions7 of the piston. in the device may beused. or not, as desired, as the machine w ll operate without it, orinstead of the pins 26 I may employ compression-springs 28 in theopenings 27 to be engaged by the side walls of the valves. (See Fig.10.) It will also be noticed that the stem 18 is of one piece throughoutand has a seat portion for the reception of the valve. This may bemodified to the extent of providing two short stems 18, suitablyattached to the valve in manner shown in Fg. 9, and employ a valve whoseouter face will be flush with the surface of the piston and be providedwith a groove 29 in its outer face for the pas- This feature sage ofsteam around the valve that it may enter the ports 9.

In the operation of the device it will be understood without furtherdescription the manner in which motive power is admitted through theports 9 for shift'ng the piston 3. The piston through its peculiarconstruction, the purposes for which it is used, and the mode ofapplying motive medium thereto is designed to move with almost uniformspeed from the beginning to the completion of its stroke. Then, again,the movement of the piston is instantaneously stopped when the devicewhich connects with its stem 5 delivers its blow. The stop is so violentthat would be destroyed.

the piston rebounds instantly. The valve has by th s time been shiftedto a posit'on which will cause the motive medium to force the piston inan opposite direction. The rebound just referred to is so violent thatwere it not for the pin or stem which controls the position of the valveand retains it in its cor rect position by the motive medium which ispermtted to act thereon the piston would bound away from the valve, andthereby change the posftion of the ports relative to the positlon of thevalve, andsuch a transposition of the ports would seriously interfereand altogether destroy the machine for successful operat'on.

Attention is now directed to the ports 9 in the piston, which, it willbe observed, pass from what may be termed the steam-chest to theopposite side of the piston and not to the ends. Were the ports to openat the ends of the piston-head instead of the side the uses for whichthis machine is intended It will be observed that where the ports openout of the pistonhead they each open into or communicate with thechambers or pockets 15 in the cylinder or member 1, which have a varyingdepth at one end of the contracted portions 16, as described. Thisarrangement permits the device connected with the stem 5 of the pistonto give the varying stroke. For instance, if the device which isattached to the stem 5 is to be operated within a boiler-tube and. ifthe tube has a piece welded to it when the means employed engages thewall of the tube where the weld occurs the length of the stroke byreason of such welding will be materially shorter than a stroke wherethere is no weld, and in water-tube boilers where the scale may varyfrom a sixteenth of an inch thick at one point to a half-inch at othersthe necessity for a varying stroke will become apparent. Now then werethe ports 9 to open out of the ends of the piston-head the varyingstroke, which is absolutely necessary, as explained, and is foundnecessary in tools in this character, it could not be accomplished, asthe motive medium emerging from the ports would act under full pressureagainst the pistonheads as soon as the valve was shifted; but by placingthe ports as shown in the drawings and by the arrangement of thecontracted or reduced chamber portions 16 of the chambers 15 the fullforce of the motive medium can only be applied against the piston-headwhen the ends of the piston have moved away from the contracted portions16 and is coincident with the deeper portions 15, and by applying themotive medium in this manner, so as not to permit the same to act on thepiston-head its entire stroke, the varying stroke of the piston desiredmay be obtained. The valve 8 after once shifted is not reshifted for areturn stroke of the piston until the face of the piston-head has passedthe deeper part of chambers 15 or member 1 and is coincident with theshallow or contracted portions 16 thereof. Then this point is reached inthe movement of the piston, it will be observed that the port foradmission of the motive medium to act on the pistonhead is wide open;but the piston-head together with the shallow portion 16 of the chamber15 form what might be termed an auxiliary valve and almost prevents themotive medium from entering behind or in front of the piston, where itis next to act thereon. From this point on to the cylinderhead thepiston will have a varying stroke, if necessary, as just enough motivemedium will be admitted through the shallow portions 16 to assist therebound of the piston and to act slightly on the stem or rod carryingthe slide-valve. In the rebound the piston is carried over until one endof the said piston is coincident with the deeper part of the chamber inthe member 1, or that chamber designated as 15, when it will be acted onby a full force of the motive medium.

The above explanation of the operation and usefulness of the device isto bring out the differences of the machines usually employed in engineconstruction and the construction herein, and it is not thoughtnecessary to go into detail and explain the stroke which is ordinarilyobtained in a piston in the usual engine construction.

I am aware that an attempt has been made and a patent issued where theoperation of a valve is to some extent controlled by looselycarried rodswhich enga e the cylinder-heads of the engine, and it is hardlynecessary for me to state that with such a construction my device wouldbe entirely inoperative, as no regularity of movement such as I aim atand obtain could be acquired by looselycarried pins, as they would neverbe in position to engage the valve and to shift it at its proper timeand would more or less leave the valve to move freely on the rebound ofthe piston, all of which, it is believed, will be understood.

I am aware that various changes may be made in the construction andcombination of features as herein employed and that details may beresorted to, and I do not wish to be confined to the details herein norto the employment of my device in its operative connection with meansactuated directly or indirectly connected with the piston.

Having thus fully described my invention, what I claim, and desire tosecure by Letters Patent of the United States, is

1. In a device of the character described, the combination of a memberhaving a cylinder portion and an inlet-port leading into the body of thecylinder and oppositely-disposed exhaust-ports leading from the cylinderand longitudinally disposed in the Walls of said member, a pistonoperatively carried in the member having inlet-ports adapted toalternately communicate with the inlet of the member and a transverseexhaust-port having communication with the exhaust-ports of the member,a slide-valve controlling the inlets of the piston and means forcontrolling the movements of said valve, substantially as specified.

2. In a device of the character described, the combination of a memberhaving a cylinder portion and an inlet-port leading into the body of thecylinder and exhaust-ports leading from the cylinder and longitudinallydisposed. in the walls of said member, a piston operatively carried inthe cylinder having steam-ports opening out of its side, chambers in thewalls of the cylinder disposed at its ends and communicating with theports of the piston, a valve, and a stem carrying the valve movableindependent of the movement of the piston, substantially as specified.

3. In a device of the character described, the combination of asteam-cylinder having reduced chambers formed in the opposite endsthereof, a piston operating in said cylinder having ports communicatingwith the chambers of the cylinder, a slide-valve movable in said pistonand means carried by the piston operatively connected with the valveadapted to actuate the same in advance of the return movement of thepiston, substantially as described.

4. A tool for the purposes herein, comprising a member having a cylinderportion, a

piston operatively carried in the member having inlet and exhaust portscommunicating with chambered or recessed portions of the member, andeach chamber having reduced or contracted portions, a stem reciprocallyarranged in the piston and a slide-valve having a positive connectionwith the stem which controls the movements thereof for opening orclosing the ports of the piston.

5. A tool for the purposes herein, comprising a member having a cylinderportion, a piston operatively carried in said cylinder having a stemdisposed to one side of its axial center to which is designed to beattached a suitable tool, also having inlet and exhaust ports openingout of its side, recessed portions of the wall of the cylindercommunieating with the inlet-ports of the piston, a stem operativelycarried in the piston having protruding ends arranged for engagementwith the end walls of the cylinder in advance of the piston and aslide-valve having a positive connection with the stem and 0011-trolling the ports of the piston, substantially as described.

6. In a tool for the purposes described, the combination of a cylinderedmember having operatively carried therein a piston having inlet andexhaust ports opening out of its sides and provided with an extensiondis posed to one side of its axial center designed &

to have attached thereto a suitable tool, chambers 15 suitably disposedin the walls of the cylinder having contracted portions 16 designed toretard the motive medium as it acts on the piston during a portion ofits stroke, a reciprocal stem passing through the piston carrying aslide-valve adapted to alternately open and close the ports of thepiston, substantially as described.

7. The mechanism for controlling the movements of a tool of thecharacter described, comprising a piston operatively carried in asuitable member having steamports opening out of its side, chambers inthe walls of the member disposed at opposite ends thereof andcommunicating with the ports of 'the piston, a slide-valve, a stem,operating longitudinally in the piston having a portion overlying thevalve, the ends of the stem arranged to engage the walls of the memberin advance of the piston for shifting the valve for closing oneinlet-port and partially opening the other whereby the piston may bereturned immediately upon its reaching the end of its stroke,substantially as and for the purposes described.

8. In a device of the character described, the combination of asteam-cylinder having oppositely-disposed chambers in its wall andcontracted portions of said chambers, a piston operating in saidcylinder having suitable steam-ports, a valve, and a stemcarrying thevalve movable independent of the movement of the piston, substantiallyfor the purposes set forth.

9. In a device of the character described, the combination of asteam-cylinder having chambers disposed in its walls at opposite endsthereof, a piston operating in said cylinder having ports communicatingwith the chambers of the cylinder, a slide-valve, and means forrelieving the blow of the valve as it abuts with portions of the piston,and a stem carrying the valve and controlling the movements thereof,substantially as described.

In testimony whereof I affiX my signature in presence of two Witnesses.

CHARLES L. CHARVAT.

Witnesses:

CHAS. W. LA PoRTE, ADA B. LA PORTE.

